Various types of scanners are known in the marketplace and in the patent literature. Most of them employ a scan trace which extends perpendicularly to the direction of displacement of the scanned substrate and thus operates in a stepped motion.
There exist two basic techniques for scanning large formats. One technique, using multiple CCD arrays, is described in "A High-Resolution, High-Speed Film Scanner System Using Optically Butted Charge-Coupled Devices (CCDs)" by Richard A. Whittlesey, SPIE, Vol. 149, Applications of Digital Image Processing (1978), pages 156-165. Another technique, employing a single CCD array which is displaced through multiple sweeps along an X-Y plane, is described in U.S. Pat. No. 4,692,812.
U.S. Pat. No. 4,525,828 to Higashiyama et al describes an optical recording device, including a magnetic recording tape, a pair of magnets and a rotary drum. The tape is driven obliquely on the outer circumference of the drum causing a laser beam to create a retrace line on the tape which is inclined with respect to the longitudinal direction of the tape.
U.S. Pat. 2,044,831 to Chereau et al describes a message scanning or reconstituting system including a curved surface or message carrier involving relative displacement of the scanning system and of the message carrier. The message carrier is caused to undergo translation movement along a given axis by moving the message oblique along the carrier, i.e. by displacing the message along a helix traced on a cylindrical surface.
U.S. Pat. No. 3,314,075 to Becker et al describes a light recording system utilizing a laser, a beam guiding assembly and a recording head and film drive for producing a series of closely spaced helically spaced traces across a film.